Excavator dipper door mounting



' Nov. 23, 1965 J. BAER EXCAVATOR DIPPER noon MOUNTING 3 Sheets-Sheet 1Filed May 2, 1962 m m m m JOSEF BAER BY @972.

/M ATTORNEY NOV. 23, 1965 J, BAER 3,219,214

EXCAVATOR DIPPER DOOR MOUNTING Filed May 2, 1962 S Sheets-Sheet 2 FIG. 4

INVENTOR.

JOSEF BAER Nov. 23, 1965 J, BAER 3,219,214

EXCAVATOR DIPPER DOOR MOUNTING Filed May 2. 1962 3 Sheets-Sheet 3INVENTOR:

JOSEF BAER I BY M574;

ATTORNEY United States Patent OfiFice 3,219,214 Patented Nov. 23, 19653,219,214 EXCAVATOR DIPPER DOOR MGUNTING Josef Baer, outl1 Milwaukee,Wis., assignor to Bucyrus- Erie Company, South Milwaukee, Wis., acorporation of Delaware Filed May 2, 1962, Ser. No. 191,794 6 Claims.(Cl. 214-145) This invention relates to the mounting of an excavatordipper door upon supporting hinge bars and more particularly to the pinconnection which joins the dipper door to the hinge bars.

In excavator clippers, a dipper door is swingably attached thereto toopen and close at the bottom thereof to discharge or contain materialsexcavated by the dipper as the use may be. The door is supported bylaterallyspaced hinge bars pivotally secured to the rear portion of thedipper. A connection, either permanent or demountable, secures thedipper door to the hinge bars.

It has been a usual practice to form the dipper door and hinge bars asan integral unit by means of casting or by fabricating them as aweldment. During digging operations, the dipper door is subjected tohigh impact loads from rocks or like objects. The integral unit is arigid structure and, as such, is unable to absorb impact loads of greatmagnitude and consequently damage frequently results, particularly atthe juncture of the door and the hinge bars.

It has also been a practice to provide a demountable connection betweenthe dipper door and the hinge bars in an attempt to overcome theinherent deficiencies of an integral unit. Many of the demountableconnections require a number of accurately machined parts; others areunable to absorb impact loads and become loosened during operation ofthe dipper which results in damage to the hinge bars and a consequentloss in operating time required to repair and maintain theseconnections.

Accordingly, an object of this invention is to provide demountable pinconnections between a dipper door and the supporting hinge bars whereina shock absorbing resilient material is disposed between the componentsof the pin connections. Such construction allows impact loads to beabsorbed within the connection and prevents the damage occasioned by thepreviously described rigid structures.

Another object of this invention is to provide a means for securing adipper door to a hinge bar wherein a minimum number of machined partsare required.

Another object of this invention is to provide a pin connection betweena dipper door and a hinge bar wherein the connection has cooperatingtapered members adapted for movement relative to each other to tightenthe connection, in which one of the members holds a resilient material,and is formed in such a manner that the resilient material is retainedin the connection.

Another object of this invention is to provide an improved taperedresilient means for maintaining a pin connection in a dipper door whensaid door is subjected to impact loadings.

This invention consists of the novel parts and of the combination andarrangement thereof which are disclosed and described in the followingspecification and drawings of which:

FIGURE 1 is a side elevation view of an excavator dipper having a doormounted on a pair of laterallyspaced hinge bars, only one of which isshown;

FIGURE 2 is a cross-sectional view of the pin connection joining thedoor and a hinge bar taken at 22 of FIGURE 1;

4 FIGURE 3 is a similar cross-section-al view of a second embodiment ofthe pin connection;

FIGURE 4 is a similar cross-sectional view of a third embodiment of thepin connection;

FIGURE 5 is an end view of a fourth embodiment of the pin connection;and

FIGURE 6 is a cross-sectional view of the pin connection of FIGURE 5taken at line 66 of FIGURE 5.

In FIGURE 1 an excavator dipper 20 is provided with a swingable door 21adapted to close the bottom of the dipper. The door 21 is mounted toswing relative to the dipper 20 by means of a pair of laterally-spacedhinge bars 22 being pivotally connected to the dipper as at 24. A latchmeans 23 is provided at the front of the dipper 20 to hold the door 21in a closed position.

Referring now to FIGURE 2, the door is supported on a surface 25 on theupper side of each hinge bar 22 along an axis of support normal tosupporting surface 25. With multiple axes of support the support isalong the resultant of the multiple axes. In actual practice the doorsupporting surface usually extends along the full length of that portionof the hinge bar adjacent the underside of the dipper door.

In a demountable connection between a dipper door and a hinge bar, it isdesirable to maintain the door supporting surface 25 of the hinge bar insupporting relationship to the underside of the door and at the sametime provide a resilient means between the door and the pin 29. InFIGURE 2, a pair of laterally-spaced mounting lugs 26 and 27 depend fromthe underside of the dipper door 21. The lugs are spaced a sufficientdistance to accommodate the width of the hinge bar 22.

Each of the lugs 26 and 27 are provided with a suitable transverseopening 28 to receive a retaining pin 29 having a head 30, a centralbody 31 and a threaded shank 32. The transverse opening in each mountinglug 26 and 27 is dimensioned to accommodate the corresponding end of theretaining pin 29, and the transverse openings 28 and the retaining pin29 is rectangular. Both the head and threaded shank have a lower surface33 and 34 respectively which is furthest from the door and shaped toconform to the surfaces 35 and 36, respectively, in the opening 28 ineach of the mounting lugs. The relative dimensions of the retaining pinand the transverse openings in the mounting lugs are proportioned topermit' movement of the pin 29 along its longitudinal axis. The pin islocked by tightening threaded nut 37 against washer 38.

A transverse opening 45 is provided in each hinge bar 22 to permit theinsertion of the central body 31 of the retaining pin 29 and to receivea metal Wedge member 40 which carries a block of resilient material 41,such as rubber of the like. The wedge member 40 is adapted to abut thehead 30 of the retaining pin 29 for adjustable axial movement andwedging action upon tightening of the nut 37. The wedge member 40 may bea small casting or metal stamping having but one machined surface 42.The interior of the wedge member is adapted to receive the block ofresilient material 41 and substantially enclose the block upon all sidesexcept one thereby eliminating the need for bonding the resilient block41 to the metal wedge member 40.

Each hinge bar 22 is provided with transverse opening having a taperedsurface 43 adapted to wedge against the surface 42 of the wedge member40. Accordingly, axial movement of the pin 29 to the right, as shown inthe drawings, will force the hinge bar 22 into contact with the bottomof the dipper door 21 and compress the resilient block 41 through thewedging action of the tapered surface 43 against wedge member 40. Thetightening of nut 37 compresses the resilient block 41 to provide aforce to maintain the hinge bar 22 in contact with the door 21 therebylocking the pin connection during operation of the dipper and the door.

Coaction of the parts of the present invention permit the resilientmaterial to absorb shocks from impact loads acting on the door, and, atthe same time, take-up of the locking means, as by tightening nut 37,prevents loosening of the pin connection and biases said block 41.

As shown in FIGURE 2, both the resilient block 41 and the cooperatingtapered surfaces 42 and 43 are disposed in series between that surface25 of the hinge bar in contact with the door 21 and surfaces 33 and 34which support the retaining pin 29 in the transverse openings 28 of themounting lugs 26 and 27. Accordingly, any compression of the resilientblock member 41 resulting from impact loads transmitted by the door andthe hinge bar will cause the components of the pin connection to bepressed together with added force.

The pin connection of the present invention also uses a minimum numberof machined component parts. Only the cooperating tapered surfaces 42and 43 of the hinge bar and wedge members need be machined to provide asmooth surface for facilitating longitudinal adjustment of the pin toeffect compression of the resilient block 41. Such adjustment will biasthe hinge bar against the bottom surface of the door and maintain it bylocking the pin connection, as by tightening nut 37.

In FIGURE 3 the door 21 is provided with mounting lugs 26 and 27depending from the underside thereof. Each of the lugs 26 and 27 areprovided with a suitable transverse opening 28 to receive retaining pin29. Said pin comprises a head 30, a central body 31, and a threadedshank 32. The transverse opening 28 in each mounting lug 26 and 27 issimilar to that described in conjunction with FIGURE 2 and isdimensioned to accommodate the respective ends of the retaining pin 29.

The pin connection of FIGURE 3 is a subspecies of FIGURE 2 and differsfrom that disclosed in FIGURE 2 in that the transverse opening 50 inhinge bar 22 is sub stantially parallel to surface 25, and allows asufficient opening for the insertion of a wedge 51 having a taperedsurface 52 for engaging surface 42 of wedge member 40 which carries ablock of resilient material 41. The transverse opening 50, havingparallel surfaces is simpler to machine in the hinge bar 22 than theopening 45 of FIG- URE 2 which has a tapered surface 43.

Axial movement of the pin 29 to the right, as shown, by tightening nut37 forces the hinge bar 22 into contact with the bottom of the dipperdoor 21 and compresses the resilient block 41 between wedge member 51and pin 29.

Any compression of the resilient member 41 resulting from impact loadstransmitted by the door and the hinge bar will cause the components ofthe pin connection to be pressed together with added force rather thancausing a separation of those components.

Referring now to FIGURE 4, a third embodiment of the invention is shownwherein the depending lugs 26 and 27 are provided with transverseopenings 61 and 62. Transverse opening 62 is preferably tapered toreceive tapered surface 63 of pin 60. Located between lugs 26 and 27 ishinge bars 22 provided with tapered transverse opening 64. The taperedsurface of opening 64 is engaged by and wedged against tapered surface63 of pin 60. Resilient mounting blocks 64 and 65 are located intransverse openings 61 and 62 respectively with resilient blocks 66 and67 in engagement with transverse openings 61 and 62 and the mountingblocks 64 and 65 in engagement with pin 60.

As nut 37 is tightened to move pin 60 axially toward washer 38, taperedsurfaces 63 and Marc in engagement and resilient blocks 66 and 67 arecompressed against the transverse openings 61 and 62 respectively,thereby resulting in the urging of hinge bar 22 against door 21. Withthe pin connection locked as by nut 37, impact loads striking the dipperand dipper door 21 do not loosen or otherwise impair the connectionbetween the hinge bars and the dipper door.

In FIGURES 5 and 6 a fourth embodiment of the invention is shown.Specifically, depending lugs 26 and 27 are provided with transverseopenings 80. The openings have convergent tapered surfaces 81 forreceiving pin 89 therethrough. The pin 89 comprises an enlarged centralportion 82, two intermediate portions 83 having tapered surfaces whichdiverge toward central portion 82, and threaded end portions 84.

Hinge bar 22 is provided with a cylindrical opening 85 to receive thecentral portion 82 of pin 89. It should be noted that in the embodimentof FIGURES 5 and 6 there is no contact between the door 21 and the hingebar 22.

To provide an impact absorbing means between the lugs 26 and 27 and thehinge bar 22, tubular resilient members 86 are inserted in the openingsbetween tapered openings and the tapered intermediate portions 83 of pin89. The resilient members 86 are forced inwardly toward the hinge bar bythe threading of nuts 87 against collars 88 to compress the resilientmembers between openings 80 and pin 89. In this manner the door isconnected to the hinge bars so that impacts on the dipper or door do notact directly on pin 89, but rather are cushioned through resilientmembers 86. As a result, such impacts do not loosen the pin connectionand the door is thereby secured to the hinge bars 22.

Thus various pin connections for a dipper door of an excavator have beendescribed, and the construction of the pin connections is such that aresilient means is wedged or compressed to maintain the connectionbetween the dipper door and the hinge bars wherein impacts do notoccasion a loosening of the pin connection.

Having described and illustrated four embodiments of the invention, itis to be understood that this invention is not to be limited to thespecific form or arrangement of parts herein described and shown, orspecifically covered by the claims.

What is claimed is:

1. In a dipper door mounting the combination comprising:

a dipper door;

a hinge bar extending beneath the door;

a pair of mounting lugs attached to and depending from said door withone on each side of said hinge bar;

a pin extending through said lugs and said hinge bar with a tighteningnut thereon;

a resilient member interposed between said pin and one of said membersthrough which the pin extends, such resilient member being substantiallyenclosed on both axial and transverse sides with respect to said pin forconstricted compression thereof in both said axial and transversedirections; and

Wedge means associated with said pin that compresses said resilientmember between said axial and transverse enclosed sides upon bringing upsaid tightening nut.

2. A mounting as in claim 1, wherein said resilient member is disposedbetween said pin and said hinge bar,

said pin has a face that acts longitudinally upon said resilient memberupon bringing up said tightening nut, and

said wedge means is interposed between the resilient member and saidhinge bar to compress the resilient member upon longitudinal movement ofthe pin in response to bringing up said tightening nut.

3. A mounting as in claim 1 wherein said resilient member is disposedbetween said pin and a mounting lug, and

said wedge means is between the pin and hinge bar to urge the pintransversely against the resilient member upon bringing up thetightening nut.

4. A mounting as in claim 1 wherein said pin forms an annular spacebetween itself and a lug through which it extends,

said resilient member is disposed in said annular space,

said wedge means comprises a tapered wall of said annular space, and

said tightening nut includes a collar bearing axially against saidresilient member,

said collar being movable against the resilient member upon bringing upsaid tightening nut to thereby compress said resilient member .betweenthe pin, lug and collar.

5. In a dipper door mounting the combination comprising:

a dipper door;

a hinge bar extending along side the door;

a pair of lugs on said door, one on each side of said hinge bar;

an axially movable pin joining said hinge bar and said lugs;

a cup shaped member having a wedge portion;

a resilient block within said cup shaped member, said block and cupshaped member being disposed between said pin and one of said memberswhich it 101118;

wedge means acting upon said cup shaped member to compress saidresilient block within said cup shaped member upon axial movement ofsaid pin; and

tightening means on said pin to draw the pin axially against the actionof said wedge means.

6. In a dipper door mounting the combination comprising:

a dipper door;

a hinge bar extending beneath the door;

a pair of mounting lugs attached to said door with one on each side ofsaid hinge bar;

a pin in said hinge bar extending through openings in said lugs withspaces between the pin and each lug;

a resilient member in each of said spaces interposed between the pin andthe associated lug;

an axially displaceable collar on each end of said pin facing axiallyinward and bearing against said resilient members; and

tightening means on said pin which move said collars against saidresilient members and compress the same between said pin and lugs.

References Cited by the Examiner UNITED STATES PATENTS 1,735,716 11/1929Anderson 214 1,883,915 10/1932 Holcomb 214145 1,981,267 11/1934Heffelfinger 214145 2,180,348 11/1939 Daniels 214145 2,335,352 11/1943Murtaugh 214146 2,561,518 7/1951 Larsen 214145 2,788,907 4/ 1957 Larsen214145 3,034,820 5/ 1962 Schwartz et al. 214147 HUGO O. SCHULZ, PrimaryExaminer.

1. IN A DIPPER DOOR MOUNTING THE COMBINATION COMPRISING: A DIPPER DOOR;A HINGE BAR EXTENDING BENEATH THE DOOR; A PAIR OF MOUNTING LUGS ATTACHEDTO AND DEPENDING FROM SAID DOOR WITH ONE ON EACH SIDE OF SAID HINGE BAR;A PIN EXTENDING THROUGH SAID LUGS AND SAID HINGE BAR WITH A TIGHTENINGNUT THEREON; A RESILIENT MEMBER INTERPOSED BETWEEN SAID PIN AND ONE OFSAID MEMBERS THROUGH WHICH THE PIN EXTENDS, SUCH RESILIENT MEMBER BEINGSUBSTANTIALLY ENCLOSED ON BOTH AXIAL AND TRANSVERSE SIDES WITH RESPECTTO SAID PIN FOR CONSTRICTED COMPRESSION THEREOF IN BOTH SAID AXIAL ANDTRANSVERSE DIRECTIONS; AND WEDGE MEANS ASSOCIATED WITH SAID PIN THATCOMPRESSED SAID RESILIENT MEMBER BETWEEN SAID AXIAL AND TRANSVERSEENCLOSED SIDES UPON BRINGING UP SAID TIGHTENING NUT.